.image-container {
      position: relative;
      display: inline-block;
    }
    .marker {
      position: absolute;
      width: 20px;
      height: 20px;
      background-color: red;
      border-radius: 50%;
      transform: translate(-50%, -50%);
      animation: pulse 1.5s infinite;
      cursor: pointer;
      box-shadow: 0 0 6px rgba(0,0,0,0.4);
    }
    @keyframes pulse {
      0% { transform: translate(-50%, -50%) scale(1); opacity: 1; }
      50% { transform: translate(-50%, -50%) scale(1.4); opacity: 0.6; }
      100% { transform: translate(-50%, -50%) scale(1); opacity: 1; }
    }